Far as I can tell it is about how Bobert thinks he has a better grasp on facts and reality than other people and is therefore superior to anybody that disagrees with him.

The Obama Administration's official Marijuana 'Myths and Facts: The Truth Behind 10 Popular Misperceptions'
Myth #1: Marijuana is harmless
Myth #2: Marijuana is not addictive
Myth #3: Marijuana is not as harmful to your health as tobacco
Myth #4: Marijuana makes you mellow
Myth #5: Marijuana is used to treat cancer andother diseases
Myth #6: Marijuana is not as popular as MDMA (Ecstasy) or other drugs among teens today
Myth #7: If I buy marijuana, I'm not hurting anyone else
Myth #8: My kids won't be exposed to marijuana..
Myth #9: There's not much parents can do to stop theirkids from experimenting with marijuana...........
Myth #10: The government sends otherwise innocent people to prison for casual marijuana use.........

Use of marijuana has adverse health, safety, social, academic, economic, and behavioral consequences. And yet, astonishingly, many people view the drug as "harmless." The widespread perception of marijuana as a benign natural herb seriously detracts from the most basic message our society needs to deliver: It is not OK for anyone to use this or any other illicit drug.Effects of marijuana use include memory loss, distorted perception, trouble with thinking and problemsolving, and anxiety. effects of marijuana use include memory loss,
distorted perception, trouble with thinking and problemsolving, and anxiety.

COGNITIVE IMPAIRMENT

That marijuana can cause problems with concentration and thinking has been shown in research funded by the National Institute on Drug Abuse (NIDA), the federal agency that brings the power of science to bear on drug abuse and addiction. A NIDAfunded study at McLean Hospital in Belmont, Massachusetts, is part of the growing body of research documenting cognitive impairment

MENTAL HEALTH PROBLEMS

Smoking marijuana leads to changes in the brain similar to those caused by cocaine, heroin, and alcohol. All of these drugs disrupt the flow of chemical neurotransmitters, and all have specific receptor sites in the brain that have been linked to feelings of pleasure and, over time, addiction. Cannabinoid receptors are affected by THC, the active ingredient in marijuana, and many of these sites are found in the parts of the brain that influence pleasure, memory, thought, concentration, sensory and time perception, and coordinated movement.